Re: Use of uninitialized valued in concatenation....
On Fri, 2003-08-22 at 17:23, B. Fongo wrote: I have a file (output_tab.pm) that I use to generate tables dynamically. Even though it serves its purpose, it goes on generating this error: Script_name.pl: Use of uninitialized value in concatenation (.) or string at output_tab.pm line 42. This is a standard perl error message. It is not related to mod_perl. You can look in the perldiag man page for a more complete explanation. - Perrin -- Reporting bugs: http://perl.apache.org/bugs/ Mail list info: http://perl.apache.org/maillist/modperl.html
Re: Use of uninitialized valued in concatenation....
B. Fongo wrote: Hello I have a file (output_tab.pm) that I use to generate tables dynamically. Even though it serves its purpose, it goes on generating this error: Script_name.pl: Use of uninitialized value in concatenation (.) or string at output_tab.pm line 42. At line 42 of your output_tab.pm module, make sure all variables being used in that line have a value before being used. For example... $null_var ||= ''; The real problem may be that your logic to assign the variable in the first place doesn't work, but you can make the error message go away with the mentioned trick. For more info on this, check out the perldoc perldiag page and look up the error message for a better explanation. Regards, Josh Josh Chamas, Founder phone:925-552-0128 Chamas Enterprises Inc.http://www.chamas.com NodeWorks Link Checker http://www.nodeworks.com -- Reporting bugs: http://perl.apache.org/bugs/ Mail list info: http://perl.apache.org/maillist/modperl.html
AW: Use of uninitialized valued in concatenation....
It is not a standard perl error message. I went through mod_perl doc at http://perl.apache.org/docs/general/perl_reference/perl_reference.html#T racing_Warnings_Reports and understand that, the error message appear if one fails to pass a value to a subroutine before using. Looking through my codes, you may have noticed that, I did pass 2 arguments to the subroutine. -Ursprüngliche Nachricht- Von: Perrin Harkins [mailto:[EMAIL PROTECTED] Gesendet: Samstag, 23. August 2003 00:10 An: B. Fongo Cc: [EMAIL PROTECTED] Betreff: Re: Use of uninitialized valued in concatenation On Fri, 2003-08-22 at 17:23, B. Fongo wrote: I have a file (output_tab.pm) that I use to generate tables dynamically. Even though it serves its purpose, it goes on generating this error: Script_name.pl: Use of uninitialized value in concatenation (.) or string at output_tab.pm line 42. This is a standard perl error message. It is not related to mod_perl. You can look in the perldiag man page for a more complete explanation. - Perrin -- Reporting bugs: http://perl.apache.org/bugs/ Mail list info: http://perl.apache.org/maillist/modperl.html
AW: AW: Use of uninitialized valued in concatenation....
Oh yes I did. I always try my script on the command line to ensure the
syntax are ok before running them on the web server with mod_perl. So
the error has to do with mod_perl. Perhaps you may want to take a look
of some examples:
I have a file (output_tab.pm) that I use to generate tables dynamically.
Even though it serves its purpose, it goes on generating this error:
Script_name.pl: Use of uninitialized value in concatenation (.) or
string at output_tab.pm line 42.
I went through this section of mod_perl docs und thought Ive understood
it, but I cant feature out the error. Ill appreciate any help.
Below is my module and a script that triggers such error.
#
output_tab.pm
#-
# Modulname: output_tab.pm
#-
use strict;
package output_tab;
use vars qw(@ISA @EXPORT);
require Exporter;
@ISA = qw(Exporter);
@EXPORT = qw(output_tab);
use db_Verbindungen;
sub output_tab{
my ($dbh,$abfrage,$columnspan, $sth,@table_head,@table_data);
($abfrage, @table_head) = @_;
$columnspan = @table_head;
print qq(table width=95% border=1 cellspacing=1
cellpadding=1 align=center);
print qq(tr bgcolor=#a9a9a9);
foreach (@table_head){
print qq(th$_/th);
}
print qq(/tr);
# Erbnisse Anzeigen
$dbh = db_Verbindungen;
$sth = $dbh-prepare($abfrage);
$sth-execute();
print qq(tr);
while(@table_data = $sth-fetchrow_array){
#my $table_data;
foreach (@table_data)
{
print qq(td bgcolor='#d0d0d0'$_/td); # Here is line 42
}
print qq(/tr);
}
print qq(trtd colspan=$columnspan
bgcolor='#d0d0d0'nbsp;/td/tr);
print qq(/table);
$sth-finish();
$dbh-disconnect();
}
1;
###
#!/usr/bin/perl -w
#
#Script: pakete_auflisten.pl
#=
use strict;
use db_Verbindungen;
use gui;
use output_tab;
my ($dbh,$abfrage,@table_head);
$abfrage = ('SELECT Gruppe, Paketname, Auftragsdatum, Status,
Statusmeldung FROM Gruppen_Software ORDER BY Auftragsdatum DESC');
@table_head = qw(Gruppe Paketname Auftragsdatum Status Statusmeldung);
# Aufruf der Methode top() des gui.pm Moduls.
top('Paketliste');
# At this stage i call the method output_tab with two arguements.
output_tab($abfrage,@table_head);
# Aufruf der Methode footer() des gui.pm Moduls.
footer();
#== ENDE==
Babs
-Ursprüngliche Nachricht-
Von: Sreeji K Das [mailto:[EMAIL PROTECTED]
Gesendet: Samstag, 23. August 2003 11:10
An: B. Fongo; 'Perrin Harkins'; [EMAIL PROTECTED]
Betreff: Re: AW: Use of uninitialized valued in concatenation
Did u check what's in line # 42 ? If u run the same
script with same params as stand-alone, do u see the
warning ?
Sreeji
--- B. Fongo [EMAIL PROTECTED] wrote: It is not a
standard perl error message. I went
through mod_perl doc at
http://perl.apache.org/docs/general/perl_reference/perl_reference.html#T
racing_Warnings_Reports
and understand that, the error message appear if one
fails to pass a
value to a subroutine before using. Looking through
my codes, you may
have noticed that, I did pass 2 arguments to the
subroutine.
-Ursprüngliche Nachricht-
Von: Perrin Harkins [mailto:[EMAIL PROTECTED]
Gesendet: Samstag, 23. August 2003 00:10
An: B. Fongo
Cc: [EMAIL PROTECTED]
Betreff: Re: Use of uninitialized valued in
concatenation
On Fri, 2003-08-22 at 17:23, B. Fongo wrote:
I have a file (output_tab.pm) that I use to
generate tables
dynamically. Even though it serves its purpose, it
goes on generating
this error:
Script_name.pl: Use of uninitialized value in
concatenation (.) or
string at output_tab.pm line 42.
This is a standard perl error message. It is not
related to mod_perl.
You can look in the perldiag man page for a more
complete explanation.
- Perrin
Want to chat instantly with your online friends? Get the FREE Yahoo!
Messenger http://uk.messenger.yahoo.com/
--
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Mail list info: http://perl.apache.org/maillist/modperl.html
Re: Use of uninitialized valued in concatenation....
B. Fongo wrote: Script_name.pl: Use of uninitialized value in concatenation (.) or string at output_tab.pm line 42. Perrin replied: This is a standard perl error message. It is not related to mod_perl. You can look in the perldiag man page for a more complete explanation. B. Fongo wrote: It is not a standard perl error message. I went through mod_perl doc at http://perl.apache.org/docs/general/perl_reference/perl_reference.html#T racing_Warnings_Reports I am sorry, but it *is* a standard Perl error message. It means exactly what it says: you concatenated or stringify an undefined value. Looking in your code (of which I do not know exactly where it starts, so line 42 is a bit of a guess) it can be either print qq(td bgcolor='#d0d0d0'$_/td); or print qq(trtd colspan=$columnspan bgcolor='#d0d0d0'nbsp;/td/tr); In the latter case, please check $columnspan to be sure it is given a defined value. For the first: you go through a list of tablerow values, can it be that a value is NULL? This would be translated into undef and hence raise this warning. Try to replace with my $val=$_||'NULL'; print qq(td bgcolor='0#d0d0d0'$val/td); --Frank -- Reporting bugs: http://perl.apache.org/bugs/ Mail list info: http://perl.apache.org/maillist/modperl.html
Re: AW: Use of uninitialized valued in concatenation....
Did u check what's in line # 42 ? If u run the same script with same params as stand-alone, do u see the warning ? Sreeji --- B. Fongo [EMAIL PROTECTED] wrote: It is not a standard perl error message. I went through mod_perl doc at http://perl.apache.org/docs/general/perl_reference/perl_reference.html#T racing_Warnings_Reports and understand that, the error message appear if one fails to pass a value to a subroutine before using. Looking through my codes, you may have noticed that, I did pass 2 arguments to the subroutine. -Ursprüngliche Nachricht- Von: Perrin Harkins [mailto:[EMAIL PROTECTED] Gesendet: Samstag, 23. August 2003 00:10 An: B. Fongo Cc: [EMAIL PROTECTED] Betreff: Re: Use of uninitialized valued in concatenation On Fri, 2003-08-22 at 17:23, B. Fongo wrote: I have a file (output_tab.pm) that I use to generate tables dynamically. Even though it serves its purpose, it goes on generating this error: Script_name.pl: Use of uninitialized value in concatenation (.) or string at output_tab.pm line 42. This is a standard perl error message. It is not related to mod_perl. You can look in the perldiag man page for a more complete explanation. - Perrin Want to chat instantly with your online friends? Get the FREE Yahoo! Messenger http://uk.messenger.yahoo.com/ -- Reporting bugs: http://perl.apache.org/bugs/ Mail list info: http://perl.apache.org/maillist/modperl.html
Re: AW: AW: Use of uninitialized valued in concatenation....
Am Sat, 23 Aug 2003 09:48:05 + schrieb B. Fongo:
foreach (@table_data)
{
print qq(td bgcolor='#d0d0d0'$_/td); # Here is line 42
}
as Frank already pointed out, your trouble is the uninitialized $_ value
you have in line 42 (which is exactly what the warning tells you, BTW).
the reason for this is very probably that @table_data contains items
that have not been initialized (= they have no value, not even an
empty value assigned to them). @table_data is filled from
database, so _check your database_. I bet you will find null values in
here.
if you don't want to output anything if the database delivers such a null
value simply replace your line 42 with
-CUT--
print qq(td bgcolor='#d0d0d0'$_/td) if $_;
-CUT--
if you want to output an empty line for null values, then do as Frank
suggested:
-CUT--
my $val=$_||'NULL'; print qq(td DEFANGED_bgcolor=0#d0d0d0$val/td);
-CUT--
and no, this has definitively absolute nothing to do with mod_perl, thats
just expected and normal perl behaviour.
happy hacking
udo
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Re: Re: AW: AW: Use of uninitialized valued in concatenation....
-CUT--
my $val=$_||'NULL'; print qq(td DEFANGED_bgcolor=0#d0d0d0$val/td);
-CUT--
This is not a very good solution. You would also catch the case where $_
is 0, which may should not happen. You would better do
foreach (@table_data) {
$_ = defined $_ ? $_ : NULL;
print qq(td bgcolor='#d0d0d0'$_/td); # Here is line 42
}
Basically you also simply could use the warnings pragma within this sub :
no warnings uninitialized;
greets, Marcel
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Re: Re: AW: AW: Use of uninitialized valued in concatenation....
On Sat, Aug 23, 2003 at 01:55:03PM +0200, Marcel Greter wrote: This is not a very good solution. You would also catch the case where $_ is 0, which may should not happen. You would better do Yes... I always fall into that pithole. I think this is because I find the 'defined(...) ? ... : ...' phrase is kinda ugly. Silly me, I know. $_ = defined $_ ? $_ : NULL; Still... I don't know if I like toying around with $_. Especially since you change the real array value (and not a copy) and this might cause problems later on (should you use the values somewhere else as well). But why are we talking about this on a mod_perl list. Sorry guys. --Frank -- Reporting bugs: http://perl.apache.org/bugs/ Mail list info: http://perl.apache.org/maillist/modperl.html
Re: AW: AW: Use of uninitialized valued in concatenation....
Frank Maas wrote: On Sat, Aug 23, 2003 at 01:55:03PM +0200, Marcel Greter wrote: This is not a very good solution. You would also catch the case where $_ is 0, which may should not happen. You would better do Yes... I always fall into that pithole. I think this is because I find the 'defined(...) ? ... : ...' phrase is kinda ugly. Silly me, I know. $_ = defined $_ ? $_ : NULL; perl 5.9 has introduced a new operator //= to make it spiffy, so you'd write the above as: $_ //= NULL; __ Stas BekmanJAm_pH -- Just Another mod_perl Hacker http://stason.org/ mod_perl Guide --- http://perl.apache.org mailto:[EMAIL PROTECTED] http://use.perl.org http://apacheweek.com http://modperlbook.org http://apache.org http://ticketmaster.com -- Reporting bugs: http://perl.apache.org/bugs/ Mail list info: http://perl.apache.org/maillist/modperl.html
AW: Use of uninitialized valued in concatenation....
OK Guys!
Thanks for all the contributions. All along, I thought mod_perl was
complaining that $_ isn't initialized. Most of the suggestions I got
points to the array (@table_data) in the loop. It is actually true that
the some of the values of the array are NULL.
Thanks again for all those suggestions.
Babs
-Ursprüngliche Nachricht-
Von: news [mailto:[EMAIL PROTECTED] Im Auftrag von Udo Rader
Gesendet: Samstag, 23. August 2003 13:00
An: [EMAIL PROTECTED]
Betreff: Re: AW: AW: Use of uninitialized valued in concatenation
Am Sat, 23 Aug 2003 09:48:05 + schrieb B. Fongo:
foreach (@table_data)
{
print qq(td bgcolor='#d0d0d0'$_/td); # Here is line 42
}
as Frank already pointed out, your trouble is the uninitialized $_ value
you have in line 42 (which is exactly what the warning tells you, BTW).
the reason for this is very probably that @table_data contains items
that have not been initialized (= they have no value, not even an
empty value assigned to them). @table_data is filled from
database, so _check your database_. I bet you will find null values in
here.
if you don't want to output anything if the database delivers such a
null
value simply replace your line 42 with
-CUT--
print qq(td bgcolor='#d0d0d0'$_/td) if $_;
-CUT--
if you want to output an empty line for null values, then do as Frank
suggested:
-CUT--
my $val=$_||'NULL'; print qq(td DEFANGED_bgcolor=0#d0d0d0$val/td);
-CUT--
and no, this has definitively absolute nothing to do with mod_perl,
thats
just expected and normal perl behaviour.
happy hacking
udo
--
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Mail list info: http://perl.apache.org/maillist/modperl.html
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Use of uninitialized valued in concatenation....
Title: Use of uninitialized valued in concatenation
Hello
I have a file (output_tab.pm) that I use to generate tables dynamically. Even though it serves its purpose, it goes on generating this error:
Script_name.pl: Use of uninitialized value in concatenation (.) or string at output_tab.pm line 42.
I went through this section of mod_perl docs und thought Ive understood it, but I cant feature out the error.
Below it my module and a script that triggers such error.
#
output_tab.pm
#-
# Modulname: output_tab.pm
#-
use strict;
package output_tab;
use vars qw(@ISA @EXPORT);
require Exporter;
@ISA = qw(Exporter);
@EXPORT = qw(output_tab);
use db_Verbindungen;
sub output_tab{
my ($dbh,$abfrage,$columnspan, $sth,@table_head,@table_data);
($abfrage, @table_head) = @_;
$columnspan = @table_head;
print qq(table width=95% border=1 cellspacing=1 cellpadding=1 align=center);
print qq(tr bgcolor=#a9a9a9);
foreach (@table_head){
print qq(th$_/th);
}
print qq(/tr);
# Erbnisse Anzeigen
$dbh = db_Verbindungen;
$sth = $dbh-prepare($abfrage);
$sth-execute();
print qq(tr);
while(@table_data = $sth-fetchrow_array){
#my $table_data;
foreach (@table_data)
{
print qq(td bgcolor='#d0d0d0'$_/td);
}
print qq(/tr);
}
print qq(trtd colspan=$columnspan bgcolor='#d0d0d0'nbsp;/td/tr);
print qq(/table);
$sth-finish();
$dbh-disconnect();
}
1;
###
#!/usr/bin/perl -w
#
#Script: pakete_auflisten.pl
#=
use strict;
use db_Verbindungen;
use gui;
use output_tab;
my ($dbh,$abfrage,@table_head);
$abfrage = ('SELECT Gruppe, Paketname, Auftragsdatum, Status, Statusmeldung FROM Gruppen_Software ORDER BY Auftragsdatum DESC');
@table_head = qw(Gruppe Paketname Auftragsdatum Status Statusmeldung);
# Aufruf der Methode top() des gui.pm Moduls.
top('Paketliste');
# At this stage i call the method output_tab with two arguements.
output_tab($abfrage,@table_head);
# Aufruf der Methode footer() des gui.pm Moduls.
footer();
#== ENDE==
Ill appreciate any help.
Babs
